89B-20

Y. C. Chen and J. JACZYNSKI. Div. of Animal & Veterinary Sciences, West Virginia Univ., PO Box 6108, Morgantown, WV 26506-6108

Antarctic krill (Euphausia superba) are small, shrimp-like crustaceans in the seas with largest biomass of any multi-cellular animal species on earth. Estimates state that 150 million metric tons (MT) of krill could be an annual sustainable harvest compared with 100 million MT of the total seafood harvest. However, small krill size and its endogenous proteases are the processing challenges, which resulted in failure of commercial krill fishery for human consumption. Our objectives were to recover krill proteins and investigate the effects of a mixture containing 2% (w/w) bovine plasma protein, 2% (w/w) potato starch, and 0.3% (w/w) polyphosphate on gelation of proteins recovered from krill. Whole krill were homogenized with water (1:6 w/v). Proteins were solubilized at pH 2.5 or 12.5 and separated from impurities using a centrifuge. Soluble proteins were precipitated at pH 5.5 and separated from water using a centrifuge. Krill pastes (78% moisture, 2% NaCl) with and without the mixture were prepared from recovered proteins and cooked in torsion tubes at 90^o C for 15 min., yielding gels. The dynamic properties of the paste, and texture and color of the gels were compared. Storage moduli (G') of acid- and alkali-treated samples without the mixture dramatically decreased at 10 to 60^o C and 40 to60 ^o C, respectively, then both G's increased from 60 to 90 ^o C. However, G' of samples with the mixture increased at 10 to 90^o C. This data indicates that the strong proteolytic activity of krill endogenous enzymes can be suppressed by BPP. The krill paste without the mixture failed to gel, while the paste with the mixture resulted in a gel, which was evaluated with texture profile analysis, Kramer shear, and torsion test. The gels were pinkish due to asthaxantin as confirmed by L*a*b* values. Our study offers a method to recover proteins from krill to develop value-added foods.

Session 89B, Aquatic Food Products: Surimi, gels and by-products
2:00 PM - 5:30 PM, Tuesday PM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana